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Defence Technology（防务技术） 2024年第1期31卷 27-40页

作者： Rui Liu Danfeng yang Kunyu Xiong ying-lei Wang Qi-Long Yan Science and Technology on Combustion Internal Flow and Thermo-structure LaboratoryNorthwestern Polytechnical UniversityXi'an710072China Xi'an Modern Chemistry Research Institute Xi'an710065China

Boron has high mass and volume calorific values,but it is difficult to ignite and has low combustion *** literature review summarizes the strategies that are used to solve the above-mentioned problems,which include coatings of boron by using fluoride compounds,energetic composites,metal fuels,and metal *** techniques include recrystallization,dual-solvent,phase transfer,electrospinning,*** one of the effective coating agents,the fluorine compounds can react with the oxide shell of boron *** comparison,the energetic composites can effectively improve the flame temperature of boron powder and enhance the evaporation efficiency of oxide film as a condensed *** and metal oxides would react with boron powder to form metal borides with a lower ignition point,which could reduce its ignition temperature.

关键词： Boron powder coating Structure and morphology Condensed phase thermal reaction Ignition and combustion

Understanding Urban Vitality from the Economic and Human Activities Perspective:A Case Study of Chongqing,China

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Chinese Geographical Science 2024年第1期34卷 52-66页

作者： yang Fiona Fan LIN Geng lei Yubing WANG ying YI Zheng School of Geography and Planning Sun Yat-sen UniversityGuangzhou510006China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519100China Chongqing Planning and Design Institute Chongqing401147China

The literature on urban vitality tends to focus on the built *** paper argues that some important processes in shaping vitality may be overlooked without examining the intensity and diversity of economic and human *** newly developed spatial big data and adopting the methods of multi-indicator measurement and spatial analysis methods,we analyzed the pattern of urban vitality in Chongqing,a provincial city in western China and,on this basis,evaluated the creation and maintenance of urban vitality from the economic and human activities *** findings indicate that the impacts of economic and human activities are positive and *** the three intensity and diversity indicators,economic intensity and population density show an effect on urban vitality stronger than that of economic ***,economic diversity has the strongest superposition or interactive effect,and is thus an important foundation *** positive effect of population density on urban vitality is largely a result of Chongqing’s jobs-housing *** case of Chongqing highlights the importance of topographic features,historical inheritance,large-scale migration,and cultural activities in shaping the distinctive vitality pattern of a *** study contends that the creation and maintenance of urban vitality can not be fully explained without incorporating the impacts of economic and human *** contributes to a comprehensive measurement of urban vitality and enriches its connotations.

关键词： urban vitality economic diversity economic intensity population density Chongqing,China

Micro RNA-331 inhibits development of gastric cancer through targeting musashi1

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World Journal of Gastrointestinal Oncology 2019年第9期11卷 705-716页

作者： lei-ying yang Guang-Le Song Xiao-Qian Zhai Li Wang Qin-Lai Liu Ming-Shun Zhou Department of Pathology Shandong First Medical UniversityTaian 271016Shandong ProvinceChina Morphological Laboratory Shandong First Medical UniversityTaian 271016Shandong ProvinceChina Department of Pathology Second Affiliated Hospital of Shandong First Medical UniversityTaian 271016Shandong ProvinceChina Department of Emergency Second Affiliated Hospital of Shandong First Medical UniversityTaian 271016Shandong ProvinceChina

BACKGROUND The molecular mechanisms involved in micro RNAs(mi RNAs)have been extensively investigated in gastric cancer(GC).However,how mi R-331 regulates GC pathogenesis remains *** To illuminate the effect of mi R-331 on cell metastasis and tumor growth in *** The q RT-PCR,CCK8,Transwell,cell adhesion,Western blot,luciferase reporter and xenograft tumor formation assays were applied to explore the regulatory mechanism of mi R-331 in *** Downregulation of mi R-331 associated with poor prognosis was detected in ***,mi R-331 suppressed cell proliferation,metastasis and tumor growth in ***,mi R-331 was verified to directly target musashi1(MSI1).In addition,mi R-331 inversely regulated MSI1 expression in GC ***,upregulation of MSI1 weakened the inhibitory effect of mi R-331 in *** mi R-331 inhibited development of GC through targeting MSI1,which may be used as an indicator for the prediction and prognosis of GC.

关键词： MicroRNA-331 Musashi1 Tumor growth Metastasis Gastric cancer

Progress and prospect of Pt-based catalysts for electrocatalytic hydrogen oxidation reactions

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Nano Research 2024年第3期17卷 960-981页

作者： Xu Zhang ying Xie lei Wang Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People’s Republic of ChinaHeilongjiang UniversityHarbin 150080China

To achieve the goals of the peak carbon dioxide emissions and carbon neutral,the development and utilization of sustainable clean energy are extremely *** fuel cells are an important system for converting hydrogen energy into electrical ***,the slow hydrogen oxidation reaction(HOR)kinetics under alkaline conditions has limited its ***,elucidating the catalytic mechanism of HOR in acidic and alkaline media is of great significance for the construction of highly active and stable *** terms of practicality,Pt is still the primary choice for commercialization of fuel *** the above basis,we first introduced the hydrogen binding energy theory and bifunctional theory used to describe the HOR activity,as well as the pH *** that,the rational design strategies of Pt-based HOR catalysts were systematically classified and summarized from the perspective of activity *** addition,we further emphasized the importance of theoretical simulations and in situ characterization in revealing the HOR mechanism,which is crucial for the rational design of ***,the practical application of Pt-based HOR catalysts in fuel cells was also *** closing,the current challenges and future development directions of HOR catalysts were *** review will provide a deep understanding for exploring the mechanism of highly efficient HOR catalysts and the development of fuel cells.

关键词： Pt-based catalysts hydrogen oxidation reaction(HOR) electrocatalytic mechanism hydrogen binding energy theory bifunctional theory

Rapid and Sensitive Biosensing of Salmonella Using Mechanical Step Rotation and Gold@platinum Nanozymatic Amplification

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Journal of Analysis and Testing 2024年第3期8卷 262-269页

作者： Meixuan Li lei Wang Ai Xu ying Ding Fengzhen yang Yanbin Li Jianhan Lin Key Laboratory of Agricultural Information Acquisition Technology Ministry of Agriculture and Rural AffairsChina Agricultural University Center of Excellence for Poultry Science University of Arkansas

Inspired by ballpoint pen, an optical biosensor is developed for detection of Salmonellausing a mechanical step rotator with a dropper to greatly simplify operation, a high gradient magnetic field with immune magnetic nanobeads to specifically separate bacteria, and immune gold@platinum nanozymes with a smartphone to sensitively detect bacteria. First, the preloaded bacterial sample is drawn by the dropper to react with the immune magnetic nanobeads through repeated squeezing and releasing of the dropper, and the rotator is successively rotated and the dropper is repeatedly squeezed and released to achieve mixing of the bacteria, magnetic nanobeads and gold@platinum nanozymes, followed by magnetic separation to remove the background. Then, the conjugates are eff ectively washed with skim milk and ultrapure water, and the substrate are rapidly catalyzed into the product. Finally, the blue product is photographed and analyzed using a smartphone to obtain the Salmonella concentration. This biosensor could detect Salmonellaas low as 56 CFU/mL in～25 min.

关键词： gold@platinum nanozyme magnetic grid separation mechanical step rotator optical biosensor Salmonella detection

Vibration properties of Paulownia wood for Ruan sound quality using machine learning methods

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Journal of Forestry Research 2024年第5期35卷 216-222页

作者： yang yang College of Art and Design Harbin UniversityHarbin 150076People’s Republic of China College of Mechanical and Electrical Engineering Northeast Forestry UniversityHarbin 150040People’s Republic of China

As an important material for manufacturing resonant components of musical instruments,Paulownia has an important influence on the sound quality of *** this paper,a model for evaluating the sound quality of Ruan based on the vibration characteristics of wood is developed using machine learning ***,the selection of materials for Ruan manufacturing relies primarily on manually weighing,observing,striking,and listening by the instrument *** in scientific theory have hindered the quality of the finished *** this study,nine Ruans were manufactured,and a prediction model of Ruan sound quality was proposed based on the raw material information of *** of a total of 180 data sets,145 and 45 sets were chosen for training and validation,*** this paper,typical correlation analysis was used to determine the correlation between two single indicators in two adjacent pairwise combinations of the measured objects in each stage of the production process in *** vibra-tion characteristics of the wood were tested,and a model for predicting the evaluation of Ruan’s acoustic qualities was developed by measuring the vibration characteristics of the resonating plate *** acoustic quality of the Ruan sound board wood was evaluated and predicted using machine learning model generalized regression neural *** results show that the prediction of Ruan sound quality can be achieved using Matlab simulation based on the vibration characteristics of the soundboard *** the model-predicted values were compared with the tradi-tional predicted results,it was found that the generalized regression neural network had good performance,achieving an accuracy of 93.8%which was highly consistent with the experimental *** was concluded that the model can accurately predict the acoustic quality of the Ruan based on the vibration performance of the soundboards.

关键词： Sound quality Wood vibration performance Paulownia wood Machine learning methods

Extended finite element-based cohesive zone method for modeling simultaneous hydraulic fracture height growth in layered reservoirs

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2960-2981页

作者： lei yang Baixi Chen Hopkins Extreme Materials Institute Johns Hopkins UniversityBaltimoreMD21218USA School of Civil Engineering The University of SydneyNSW2006Australia Department of Mechanical Engineering University of Wisconsin-Madison1513 University AvenueMadisonWI53706-1572USA Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

In this study,a fully coupled hydromechanical model within the extended finite element method(XFEM)-based cohesive zone method(CZM)is employed to investigate the simultaneous height growth behavior of multi-cluster hydraulic fractures in layered porous reservoirs with modulus *** coupled hydromechanical model is first verified against an analytical solution and a laboratory ***,the fracture geometry(***,aperture,and area)and fluid pressure evolutions of multiple hydraulic fractures placed in a porous reservoir interbedded with alternating stiff and soft layers are investigated using the *** stress and pore pressure distributions within the layered reservoir during fluid injection are also *** simulation results reveal that stress umbrellas are easily to form among multiple hydraulic fractures’tips when propagating in soft layers,which impedes the simultaneous height *** is also observed that the impediment effect of soft layer is much more significant in the fractures suppressed by the preferential growth of adjoining *** that,the combined effect of in situ stress ratio and fracturing spacing on the multi-fracture height growth is presented,and the results elucidate the influence of in situ stress ratio on the height growth behavior depending on the fracture ***,it is found that the inclusion of soft layers changes the aperture distribution of outmost and interior hydraulic *** results obtained from this study may provide some insights on the understanding of hydraulic fracture height containment observed in filed.

关键词： Hydraulic fracturing Layered reservoir Simultaneous height growth In situ stress Fracture spacing Extended finite element method(XFEM) Cohesive zone method(CZM)

The Short-Duration Heavy Rainfall in Different Quadrants of Northeast China Cold Vortices

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Journal of Meteorological Research 2024年第2期38卷 321-338页

作者： lei yang Yongguang ZHENG Liaoning Meteorological Disaster Monitoring and Early Warning Center Shenyang 110166 National Meteorological Centre China Meteorological AdministrationBeijing 100081 China Meteorological Administration Tornado Key Laboratory Foshan 528315

The Northeast China cold vortex(NCCV)is one of the main synoptic-scale systems causing short-duration heavy rainfall(SDHR)in Northeast *** conditions(e.g.,water vapor,instability,and vertical wind shear)are known to be distinctly different over the four quadrants of NCCVs,rendering prediction of the SDHR related to NCCVs(NCCV_SDHR)more *** on 5-yr hourly rainfall observations from 3196 automatic weather stations and ERA5 reanalysis data,10,232 NCCV_SDHR events were identified and divided into four quadrant groups according to their relative position to the center of the NCCV(CVC).The results show that the southeast quadrant features the highest frequency of SDHR,with stronger intensity,longer duration,and wider coverage;and the SDHR in different quadrants presents different formation mechanisms and varied temporal evolution.A new coordinate system is established relative to the CVC that uses the CVC as the origin and the radius of the NCCV(r CV)as the unit *** this new coordinate system,all of the NCCV_SDHR events in the 5-yr study period are *** is found that the occurrence frequency of NCCV_SDHR initially increases and then decreases with increasing distance from the *** highest frequency occurs mainly between 0.8 and 2.5 times r CV from the CVC in the southeast *** can be attributed to the favorable conditions,such as convergence of the low-level shear line and abundant water vapor,which are concentrated in this ***,high-frequency NCCV_SDHR larger than 50 mm(NCCV_SDHR50)is observed to be closer to the *** NCCV_SDHR50occurs,the NCCV is in closer proximity to the subtropical high,resulting in stronger low-level convergence and more abundant water ***,there are lower lifting condensation levels and stronger 0-6-and 0-1-km vertical wind shears in these *** findings provide a valuable reference for more accurate prediction of NCCV_SDHR.

关键词： Northeast China cold vortex short-duration heavy rainfall statistical characteristics environmental conditions

Research advancement of DNA-based intelligent hydrogels:Manufacture, characteristics, application of disease diagnosis and treatment

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Chinese Chemical Letters 2024年第10期35卷 92-101页

作者： Zhe-Han yang Jie Yin lei Xin Yuanfang Li Yijie Huang Ruo Yuan ying Zhuo Chongqing Key Laboratory of Catalysis and Functional Organic Molecules College of Environment and ResourcesChongqing Technology and Business UniversityChongqing 400067China Key Laboratory of Luminescence and Real-Time Analytic Chemistry(Southwest University) Ministry of EducationCollege of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China

DNA-based hydrogels are exceptional materials for biological applications because of their numerous advantages such as biodegradability,biocompatibility,hydrophilicity,super absorbency,porosity,and *** these advantages,the ability of DNA-based hydrogels to respond to specific physical and chemical triggers and undergo reversible phase transitions has garnered significant attention in the fields of disease diagnosis(biosensors)and treatment(drug delivery).This article focuses on the recent advancements in the research of DNA-based hydrogels and discusses the different types of these hydrogels,the synthetic methods,their unique properties,and their applications in biosensors and drug *** types of DNA hydrogels are categorized based on their building blocks,and the process of synthesis as well as the unique characteristics of DNA-based hydrogels are ***,DNA-based responsive hydrogels utilized as intelligent materials for the development of biosensors are ***,this article also presents the current status of DNA-based responsive hydrogels in drug delivery for cancer treatment,wound healing,and other therapeutic ***,this paper discusses the current challenges in expanding the practical application of DNA-based hydrogels.

关键词： DNA-based hydrogel Intelligent hydrogel Manufacture Characteristics Diseasediagnosis and treatment

Optimal investment based on relative performance and weighted utility

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 328-342页

作者： WANG lei DONG ying-hui HUA Chun-rong Department of Mathematics Suzhou University of Science and TechnologySuzhou 215009China Changshu Institute of Technology Changshu 215500China

This paper studies the optimal portfolio allocation of a fund manager when he bases decisions on both the absolute level of terminal relative performance and the change value of terminal relative performance comparison to a predefined reference point. We find the optimal investment strategy by maximizing a weighted average utility of a concave utility and an Sshaped utility via a concavification technique and the martingale method. Numerical results are carried out to show the impact of the extent to which the manager pays attention to the change of relative performance related to the reference point on the optimal terminal relative performance.

关键词： relative performance weighted utility S-shaped utility concavification